Global warming refers to the increase in the average temperature of the Earth, namely the air near the Earth's surface as well as the water in the oceans. Global warming is a recent phenomenon, happening since the mid-20th century and its projected continuation. Global surface temperature increased 0.74 ± 0.18 °C (1.33 ± 0.32 °F) between the start and the end of the 20th century.
Few people debate global warming per se, but two polarized opinions exist in regards to what causes it. The Intergovernmental Panel on Climate Change (IPCC) and most scientists conclude that most of the observed temperature increase since the middle of the 20th century has been caused by increasing concentrations of greenhouse gases resulting from human activity such as fossil fuel burning and deforestation. On the other hand, a few scientists disagree that greenhouse gases produce global warming or that global warming is occurring.
Want to know more?
- Wikipedia - Global warming
- An introductory article to global warming.
- Wikipedia - Global warming (opposing views)
- An introduction to the main arguments against the establishes view on global warming.
- National Geographic - The carbon bathtub cycle
- This article by National Geographic uses a bathtub as a metaphor for explaining the CO2 life cycle on Earth. It also provides a link to an interesting climate change simulator, which you can use for predicting how climate would be in a near future if you were to make changes in one or more variables at present. [The printed article is in NATIONAL GEOGRAPHIC (2009). The carbon bathtub. National Geographic 2009, vol.216, n.6, pp.26-29.]
- National Geographic - Changing rain patterns
- This article in National Geographic focuses on the changing rain patterns due to global warming, and predict future trends in rain fallout. [The printed article is in KOLBERT Elizabeth (2009). Outlook: extreme. National Geographic 2009, vol.215, n.4 (April), pp.60-65.]